Seven-year veteran Ryan Cook has been added to provide some depth on the offensive line.
The Cowboys sent a seventh-round pick in 2013 to Miami for Cook, who started against the Cowboys at center in Wednesday's preseason finale.
Cook was likely to be released by the Dolphins in Friday's final cuts, but comes to Dallas where he is expected to be a backup center/guard and possibly tackle, where the majority of his 40 career starts have occurred.
The Cowboys have suffered injuries to all three of their projected centers since the start of camp, including starter Phil Costa, who missed the first three preseason starts with back issues.
Bill Nagy (ankle) has been waived/injured and claimed by the Lions and Kevin Kowalski (ankle) is on Reserve PUP and will miss the first six weeks of the season.
David Arkin, a fourth-round pick in 2011 who was inactive for all 16 games for the Cowboys, has been working at center all camp and has had his struggles. He was not one of the 21 players who turned in their playbooks on Thursday as expected cuts. But with Cook now in the fold, the Cowboys will likely replace either Arkin or veteran guard Derrick Dockery.
Cook, 29, was a second-round pick of the Vikings in 2006 who played six years in Minnesota. He has starts at right tackle and right guard, but recently has worked more at center. He joined the Dolphins this year but wasn't expected to make the roster.